Method for bringing a number of substances together by remote control and a device for carrying out said method

ABSTRACT

The substances to be brought together are placed in a vertical cell, at least that substance which is placed at the bottom of the cell being in the liquid state at the moment of contacting. A hydraulic seal consisting of a liquid having a density of higher value than the liquid-state density of the substance which is located immediately beneath said liquid is pierced by means of a perforator and caused to tilt downwards. The entire seal thus reaches the bottom of the cell and the reactants are thus brought together. The perforator is formed from magnetic material and set in motion as a result of the force produced by a magnetic induction gradient which is created by external means.

UnIted States Patent 1191 1111 3,724,820

Bonjour et al. [451 Apr. 3, 1973 [54] METHOD FOR BRINGING A NUMBER 3,240,328 3/1966 Matteuzzi ..206/47 A igg fggg FOREIGN PATENTS OR APPLICATIONS FOR CARRYING OUT SAID METHOD 1,151,246 10/1959 Germany ..259/DIG. 46

[75] Inventors: Emmanuel Bonjour, Grenoble; Michel Couach, Lyon, both of France I [7 3] Assignee: Commissariat A LEnergie Atomique, Paris, France [22] Filed: Apr. 7, 1971 [21] Appl. No.: 131,866

[52] US. Cl. ..259/l14, 23/230 R, 23/252 R, 23/253 R, 23/259, 73/190, 259/DIG. 46 [51] Int. Cl. ..B0lf 13/08, B0lf 3/20, GOln 33/00 [58] Field of Search ..259/DIG. 46, 19, 114; 206/47 A [56] References Cited UNITED STATES PATENTS 2,982,396 Y 5/1961 Shihadeh ..206/47 A Primary Examiner-William l. Price Assistant Examiner-Alan I. Cantor Att0rney-Cameron, Kerkam & Sutton [5 7] ABSTRACT The substances to be brought together are placed in a vertical cell, at least that substance which is placed at the bottom of the cell being in the liquid state at the moment of contacting. A hydraulic seal consisting of a liquid having a density of higher value than the liquidstate density of the substance which is located immediately beneath said liquid is pierced by means of a perforator and caused to tilt downwards. The entire seal thus reaches the bottom of the cell and the reactants are thus brought together. The perforator is formed from magnetic material and set in motion as a result of the force produced by a magnetic induction gradient which is created by external means.

8 Claims, 4 Drawing Figures mlimmm 1975 saw 2 [1F 2 FIG. 3

METHOD FOR BRINGING A NUMBER OF SUBSTANCES TOGETHER BY REMOTE CONTROL AND A DEVICE FOR CARRYING OUT SAID METI-IOD This invention relates to a method for brining together by remote control at least two substances which are capable of reacting with each other and to a device for carrying out said method.

The operation involved in bringing a number of substances together is a general problem which is encountered especially in laboratories. This operation is important for initiating phenomena which result from the combination of said substances. Although the operation is frequently carried out without any special precautions, there are cases in which it is essential to be able to select the initial instant of contact, in particular when it is of interest to study the kinetics of physical or chemical phenomena which result from said contact this is the case, for example, in calorimetry which is employed for measuring heats of reaction and one of the main objects of the invention is accordingly to permit the possibility of choosing this initial instant. A further object lies in the fact that said contact is made by minimizing the disturbance which can be caused by the external medium.

This invention is directed to a method for bringing a number of substances together by remote control and permitting the achievement of the aims mentioned above, said substances being placed in a vertical cell and at least that substance which is placed at the bottom of said cell being in the liquid state at the moment of contacting.

This method is essentially characterized in that a hydraulic seal constituted by a liquid having a density of higher value than the liquid-state density of the substance which is located immediately beneath said liquid is perforated in order to cause tilting of said seal which reaches'the bottom of the cell in its entirety and in order that the reactants may thus be brought together, said perforation being carried out by making use of suitable means.

The perforation is ensured by means of an element formed of magnetic material having the requisite shape to permit adaptation to particular cases either in regard to the shape of the cell or the nature of the reactants. For example, the perforator can have an elongated and tapered shape or can be in the form of a cylinder, a piston and the like.

A further property of the method according to the invention lies in the fact that, at the moment of introduction of the hydraulic seal, the substance which is placed beneath said seal is in solid form, said substance being then liquefied prior to tilting of said seal.

The invention is also concerned with a device for carrying out said method and characterized in that said device comprises a vertical cell having a vertical axis of revolution and containing at least one liquid hydraulic seal which separates at least two substances to be contacted, a perforator of magnetic material and external means for setting said perforator in motion.

In accordance with the' invention, the perforator is set in motion by surrounding the cell with an induction coil which creates a magnetic induction gradient and this gives rise to an electromagnetic force which causes either upward or downward displacement of the perforator within the cell.

In a preferred embodiment of the device, the internal wall of the cell is burnished or provided with a coating which can consist of a deposited film layer having'a silicone or teflon base.

Further properties and advantages of the invention will become apparent from the following description, reference being made to the accompanying drawings, in which FIG. 1 illustrates a device according to the invention in the general case in which the cell contains two reactants 1 and 2 separated by a hydraulic seal 3 and in which the perforator 4 is set in motion by electromagnetic means FIG. 2 illustrates a device according to the invention in the particular case in which the cell contains the two reactants 10 (water) and 1 l (lithium chloride or potassium chloride) which are separated by a hydraulic seal 12 (liquid mercury) and in which the perforator is set in motionby electromagnetic means FIGS. 3 and 4 illustrate a device according to the invention in two initial and final stages of operation and in the case in which the motion of the perforator takes place in the upward direction.

It is wholly apparent that the scope of the invention is not limited to calorimetric measurements or to the examples described which are only particular applications of the method. In particular, the device is not limited to the contacting of two substances but is wholly suited for mixing a number of substances it is only necessary to increase the number of liquid hydraulic seals and the device may thus readily serve to measure the heats of a ternary mixture.

The cell containing the reactants 1 and 2 is illustrated in FIG. 1 and has a cylindrical shape while the diameter of said cell is in the vicinity of a few millimeters. Prior to start-up of the reaction, the elements contained in the cell have the general arrangement which is indicated the reactants l and 2 are separated by a liquid seal 3 which ensures fluid-tightness between said reactants a needle 4 of magnetic material constitutes the perforator and is intended to pierce the hydraulic seal by initiating the downward motion of the needle within the cell at the desired moment said motion results from the force produced by means of the magnetic induction gradient of an inductance coil 5 which surrounds the cell. Said motion can also be carried out by means of a magnet 20 which is located at the level of the lower portion of the cell. It is important to note that at least one of the substances to be contacted should be in the liquid state at the moment of contacting said substance will preferentially be placed at the bottom of the cell. The hydraulic seal consists of a liquid having a density which is higher than that of the liquid 1 for example, it is possible to make use of mercury, an alloy of mercury, methylene iodide, thallium formiate. The second reactant 2 which can be either a liquid or a solid as desired is located above the seal 3 and may be replaced by a catalyst if necessary. The substance 1 is placed in the cell either in solid or liquid form however, it is important to ensure that the substance 1 should be in solid form at the moment of introduction of the hydraulic seal this condition can usually be satisfied by bringing the substance 1 to a sufficiently low temperature. Moreover, fluid-tightness between the spaces provided for the products 1 and 2 respectively must be ensured by the liquid seal 3 in order to meet this requirement, the internal surface of the cell is treated and can thus be burnishedor provided with a coating having a silicone or teflon base. Finally, the substance 2 is introduced in either solid or liquid form, depending on the test conditions. I

Assuming that it is desired to carry out a reaction between the products 1 and 2 as has been stated earlier, the liquid seal is introduced on the product 1 in the solid state; the thickness of the liquid seal must be sufficient to ensure fluid-tightness with respect to the cylindrical wall of the cell.

It will accordingly be assumed also that the substance 1 is solid and at a temperature below C. After introduction of the liquid seal, the product 2 and the needle 4 can either be introduced directly or the temperature of the system consisting of solid substance 1 liquid seal can be permitted to rise the system consisting of liquid substance 1 liquid seal is in stable mechanical equilibrium in the vertical position although the density of the seal is higher than 1 this is due to the fluid-tightness of the seal with respect to the cell wall the substance, 2 and the needle 4 can then be introduced whilst the system remains in a state of equilibrium. When "the system is at the desired temperature, the reaction can then be started by placing the complete unit in a magnetic induction gradient in order that the needle 4 whose length is greater than the total thickness of the liquid hydraulic seal and the reactant which is located beneath said seal and which is permeable to the lines of force 6 should be attracted towards the bottom of the cell said lines of force are produced by excitation of an induction coil which is located at the lower portion of the cell. Displacement of the needle has the effect of piercing the liquid seal, thereby tilting the phase 3 and reversing the phases 1 and 3 under the action of their difference in density this process makes it possible to have a quantitative reaction between the products 1 and 2 in fact, at the moment of tilting, the liquid seal occupies the entire lower end of the cell and displaces the phase 1 in the upward direction, and this permits mixing of the phases 1 and 2 in known proportions.

One advantage of the invention lies in the use of a needle formed of magnetic material and of a magnetic induction gradient. After having reversed the two phases 1 and 3 and thus mixed the two phases 1 and 2, this mixture can be perfected by agitation carried out by imparting a movement to the needle 4 by means of the magnetic induction gradient.

The cell in the initial state is shown in FIG. 3 the reagentsl and 2 are separated by the hydraulic seal 3. A perforator 18 of cylindrical shape is immersed in the substance 1 which occupies the bottom compartment of the cell.

When the upwardly directed magnetic field 19 is applied, the perforator l8 pierces the hydraulic seal 3 and tipsthis latter into the bottom of the cell. The two substances 1 and 2 are then mixed and the hydraulic seal 3 is at the bottom of the cell. This final state is illustrated in FIG. 4.

Without any limitation being implied, there will now be given two examples of application of the method according to the invention to the measurement of enthalpies of a particular reaction at different temperatures. In order thatthe process and device of the invention may be clearly understood, reference will be made to the accompanying FIG. 2 which illustrates a device for measuring the heat of dilution of mineral salts in water.

' EXAMPLE 1 The reaction capsule is a pyrex tube having an external diameter of 3.7 mm, an internal diameter of 3.1 mm

and a length of 8 mm. A drop of water 10 is introduced into the bottom of the cell and transformed into ice so as to form an ice bead. The operation is continued by introducing a liquid seal 12 which consists of mercury in this particular example. During this introduction, care is taken to place the cell in a zone in which the temperature is in the vicinity of 10 C in order to prevent melting of the ice. After introduction of the seal, the system canbe allowed to revert to room temperature at which it will be in a stable mechanical state. The thickness of the seal is approximately 2 to 3 mm and ensures perfect fluid-tightness with respect to the pyrex tube.

In the example under consideration, the temperature of 10 C is only given by way of indication and simply makes it possibleto prevent melting of the ice during introduction of the seal in liquid form. In this specific instance, it is quite possible to operate at a temperature which is lower than the melting point of mercury 3 8.87" C), thereby resulting in solidification of the mercury as this latter is introduced. If the system is heated, melting of the mercury first takes place. Fluid-tightness is then achieved between the seal and the reaction cell. When the system has reverted to room temperature (water liquid mercury) which is a mechanically stable state, the salt 11 consisting of a predetermined quantity of lithium chloride can be introduced as well as the magnetic needle 13 (diameter 35/ 100 mm, length 4 mm). .The capsule is then closed at 14 by crimping. In the case herein described, the introduction of the second reaction product at room' temperature makes it possible to eliminate parasitic condensation of moisture. The reaction capsule which must always be in a vertical position and handled with care is then introduced into a metallic cell 15 which is in turn closed by crimping. The complete assembly can then be cooled to the temperature of liquid nitrogen, thus makin g it possible to solidify the system and facilitating subsequent handling operations. The capsule is then inserted into a power-compensated differential calorimeter 16 having a programmed temperature rise. An induction coil 17 is placed around the adiabatic calorimeter enclosure mm in diameter) and installed in such a manner as to ensure that the cell containing the reaction system isplaced in a magnetic induction gradient. The dilution reaction can then be started at the desired temperature provided that this latter is higher than 0 C by supplying the induction'coil at intervals of a few seconds at a high current intensity (400 amps) the magnetic force which is exerted on the needle formed of magnetic material and contained in the reaction cell is then sufficient to pierce the mercury seal and to cause tilting of the system.

The method herein described offers the possibility of starting the dilution reaction at any temperature above 0 C, that is to say of measuring the enthalpy of the reaction at different temperatures.

If the recording of thermal effects as a function of temperature is studied during heating of the reaction system, there can be observed two endothermic peaks which correspond successively to melting of the mercury at 38.8 C and to melting of the ice. An exothermic peak which corresponds to dilution of the lithium chloride is also observed.

EXAMPLE 2 A second example is provided by the measurement of heats of mixing of benzene and carbon tetrachloride. This latter is preferably placed at the bottom of the cell and is maintained at a temperature below its melting point which is 23 C during introduction of the mercury which constitutes the liquid seal heating to room temperature provides a mechanically stable system in the vertical position by means of liquid carbon tetrachloride surmounted by mercury which ensures fluid-tightness with respect to the pyrex capsule. The benzene is then introduced in liquid form as well as the needle of magnetic material the experimental procedure is the same as the mode of operation described in the first example. Starting from low temperatures, the following sequence will be observed melting of the mercury at 38.8 C, melting of the carbon tetrachloride at 23 C and finally melting of the benzene at 5.5 C. Starting from this temperature, it is then possible to initiate the mixing reaction by placing the system in a magnetic induction gradient. The method makes it possible on the one hand to obtain the heats of mixing as a function of the concentration at a predetermined temperature and on the other hand the heats of mixing as a function of temperature at a constant concentration.

In the method according to the invention, the cell can be fabricated from titanium or titanium alloys which have good corrosion resistance. The cell can also be formed fromtitanium and overlaid with a sprayed coating of copper. It is also possible to employ a copper cell having an internal surface which is protected by a coating of titanium, platinum or indium.

The magnetic material which constitutes the perforator can be an alloy of iron and nickel or alternatively an alloy ofv cobalt and platinum containing 77 percent platinum.

The method according to the invention is primarily applicable to calorimetric measurements such as the measurements performed inthe differential calorimeter which is described in the French patent filed by the present applicant on May 4, 1964 and entitled Method of Thermal Analysis and Device for the Appli cation of Said Method and granted under US. Pat. No. 1.363.283.

We claim:

1. A method for bringing at least two substances together by remote control, comprising the steps of placing a first substance in a vertical cell, said first substance at the bottom of said cell being in the liquid state, locating a hydraulic seal of a liquid having a density of higher value than the liquid-state density of said first substance above said first substance in the cell,

placing a second substance in the cell above said hydraulic seal perforating and tilting said seal, moving said seal to the bottom of the cell in its entirety thereby bringing the substances together, said perforation step being carried out by an e ement of magnetic material 3. A method according to claim 1, including the I further step of mixing the substances by agitation caused by movement of said magnetic material.

4. A device for bringing substances together by remote control comprising a vertical cell having a vertical axis of revolution, at least one liquid hydraulic seal in said cell separating at least twosubstances to be contacted, a perforator of magnetic material in said cell and means external of said cell for setting said perforator in motion in said cell.

5. A device according to claim 4, including electromagnetic means for setting said perforator in motion including an induction coil surrounding said cell.

6. A device according to claim 4, said means for setting said perforator in motion including a magnet adjacent the lower portion of said cell.

7. A device according to claim 4, said hydraulic seal having a thickness of from 2 to 3 mm. to ensure fluidtightness between the substances to be contacted.

8. A device according to claim 4, the internal wall of said cell being polished whereby said hydraulic seal provides fluid-tightness between the the substances to be contacted. 

1. A method for bringing at least two substances together by remote control, comprising the steps of placing a first substance in a vertical cell, said first substance at the bottom of said cell being in the liquid state, locating a hydraulic seal of a liquid having a density of higher value than the liquid-state density of said first substance above said first substance in the cell, placing a second substance in the cell above said hydraulic seal perforating and tilting said seal, moving said seal to the bottom of the cell in its entirety thereby bringing the substances together, said perforation step being carried out by an element of magnetic material set in motion by a magnetic induction gradient external of the cell.
 2. A method according to claim 1 wherein, at the moment of introduction of said hydraulic seal, said first substance beneath said seal is solid, including the step of liquifying said first substance prior to tilting of said seal.
 3. A method according to claim 1, including the further step of mixing the substances by agitation caused by movement of said magnetic material.
 4. A device for bringing substances together by remote control comprising a vertical cell having a vertical axis of revolution, at least one liquid hydraulic seal in said cell separating at least two substances to be contacted, a perforator of magnetic material in said cell and means external of said cell for setting said perforator in motion in said cell.
 5. A device according to claim 4, including electromagnetic means for setting said perforator in motion including an induction coil surrounding said cell.
 6. A device according to claim 4, said means for setting said perforator in motion including a magnet adjacent the lower portion of said cell.
 7. A device according to claim 4, said hydraulic seal having a thickness of from 2 to 3 mm. to ensure fluid-tightness between the substances to be contacted.
 8. A device according to claim 4, the internal wall of said cell being polished whereby said hydraulic seal provides fluid-tightness between the the substances to be contacted. 